Related Experiment Video

Updated: Apr 4, 2026

Quantifying Yersinia pseudotuberculosis Type III Secretion System Activity Following Iron Starvation and Anaerobic Growth
08:36

Quantifying Yersinia pseudotuberculosis Type III Secretion System Activity Following Iron Starvation and Anaerobic Growth

Published on: May 31, 2024

1.0K

Role of the Yersinia YopJ protein in suppressing interleukin-8 secretion by human polymorphonuclear leukocytes

Justin L Spinner1, Aaron M Hasenkrug1, Jeffrey G Shannon1

  • 1Laboratory of Zoonotic Pathogens, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 905 S. 4th St., Hamilton, Montana 59840, USA.

Microbes and Infection
|September 13, 2015
PubMed

Insights

Yersinia pestis virulence factors, specifically YopJ, suppress human immune cells (PMNs) from releasing interleukin-8 (IL-8). This inhibition of IL-8 may delay immune cell recruitment during plague infections.

Area of Science:

  • Immunology
  • Microbiology
  • Bacterial Pathogenesis

Background:

  • Polymorphonuclear leukocytes (PMNs) are crucial for immune responses to infection, producing cytokines that regulate innate and adaptive immunity.
  • Yersinia species are pathogenic bacteria that can cause significant infections, including plague.
  • Cytokine production by PMNs plays a vital role in controlling bacterial infections.

Purpose of the Study:

  • To investigate the cytokine response of human PMNs when incubated with pathogenic Yersinia species.
  • To determine the role of the pCD1 virulence plasmid and its encoded Yop proteins in modulating PMN cytokine production.
  • To identify specific Yop proteins involved in the suppression of interleukin-8 (IL-8) secretion.

Main Methods:

  • Incubation of human PMNs with various Yersinia pestis strains, including wild-type, pCD1-negative, and strains with specific Yop gene deletions.
  • Quantification of cytokine levels, particularly IL-8 (CXCL8), secreted by PMNs using established assays.
  • Comparison of cytokine responses induced by Y. pestis and enteropathogenic Yersinia species.

Main Results:

  • Yersinia pestis strains possessing the pCD1 virulence plasmid significantly inhibited IL-8 production by human PMNs compared to pCD1-negative strains.
  • PMNs incubated with pCD1-negative Y. pestis secreted substantially higher levels of IL-8.
  • Deletion of yopJ in Y. pestis strains restored significant IL-8 production, indicating YopJ's critical role in IL-8 suppression.
  • Enteropathogenic Yersinia species also inhibited IL-8 secretion, with avirulent strains inducing high IL-8 levels.

Conclusions:

  • Virulence plasmid-encoded Yop effectors, particularly YopJ, are responsible for suppressing IL-8 secretion from human PMNs during Yersinia infection.
  • The suppression of the chemotactic IL-8 response by Y. pestis may contribute to the characteristic delayed PMN recruitment observed in bubonic plague.
  • Understanding these immune evasion mechanisms is crucial for developing effective treatments against Yersinia infections.
Keywords:
CXCL8IL-8NeutrophilPlagueYersiniaYopJ

More Related Videos

Analysis of Yersinia enterocolitica Effector Translocation into Host Cells Using Beta-lactamase Effector Fusions12:23

Analysis of Yersinia enterocolitica Effector Translocation into Host Cells Using Beta-lactamase Effector Fusions

Published on: October 13, 2015

9.0K
Electroporation-Based CRISPR-Cas9-Mediated Gene Knockout in THP-1 Cells and Single-Cell Clone Isolation09:29

Electroporation-Based CRISPR-Cas9-Mediated Gene Knockout in THP-1 Cells and Single-Cell Clone Isolation

Published on: February 28, 2025

4.0K

Related Concept Videos

Inhibitors of Bacterial Protein Synthesis01:25

Inhibitors of Bacterial Protein Synthesis

Aminoglycosides constitute a highly potent class of bactericidal antibiotics that exert their antimicrobial effects by targeting the bacterial ribosome, specifically disrupting protein synthesis. These polycationic molecules consist of amino-modified sugars linked via glycosidic bonds to an aminocyclitol core such as 2-deoxystreptamine or streptamine. Their strong positive charges facilitate tight binding to the negatively charged phosphate backbone of ribosomal RNA (rRNA), primarily at the 16S...
54
The JAK-STAT Signaling Pathway01:20

The JAK-STAT Signaling Pathway

Several cytokine receptors have tightly bound Janus kinase or JAK proteins attached at their cytosolic tail. Small signaling molecules such as cytokines, growth hormones, or prolactins bind to the cytokine receptors and initiate their dimerization. The dimerization brings the cytosolic JAKs together that trans-phosphorylate and activates each other. The activated JAKs now phosphorylate cytosolic tails of the cytokine receptors, which serve as binding sites for adaptor proteins such as  SH2...
14.0K
Regulation of Bacterial Virulence01:28

Regulation of Bacterial Virulence

Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...
39
Inhibitors of Viral Protein Synthesis01:30

Inhibitors of Viral Protein Synthesis

Protein synthesis is indispensable for viral replication, as viruses lack the cellular machinery required for this process and must hijack the host's translational apparatus. In response, host cells deploy a critical innate immune defense involving interferons, specialized cytokines that play a central role in inhibiting viral propagation.Upon viral detection, infected cells release interferons that bind to receptors on adjacent uninfected cells, activating the JAK-STAT signaling pathway and...
32
T Cell Types and Functions01:24

T Cell Types and Functions

When T cells with CD4 markers are activated, they give rise to two types of effector cells: helper T cells and regulatory T cells. Meanwhile, T cells with CD8 markers differentiate into effector cytotoxic T cells. The differentiation of CD4 T cells into helper T cell subsets, such as Th1, Th2, and Th17 cells, is dependent on the antigen type, antigen-presenting cell, and regulatory cytokines.
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
3.3K
Antimicrobial Proteins01:23

Antimicrobial Proteins

Antimicrobial proteins are important components of the immune system. They aid the body in combating pathogens by either killing them directly or hindering their replication processes. Four main types of antimicrobial substances are interferons, the complement system, iron-binding proteins, and antimicrobial proteins.
Interferons
Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
15.4K